Trailing 29-28, England sent on Shane Geraghty at fly-half and Rob Webber at hooker, while fellow replacements James Haskell, Ben Youngs and Dan Ward-Smith also appeared on the hour.
As well as youngsters such as Ben Youngs, Chris Ashton, Ben Foden, Dan Cole and Courtney Lawes forcibly asserting their Test credentials, Johnson also took heart from the contributions of others to the second-string side.